diff --git a/changelogs/unreleased/rd-fix-case-sensative-email-conf-signup.yml b/changelogs/unreleased/rd-fix-case-sensative-email-conf-signup.yml
new file mode 100644
index 00000000000..69695e403a9
--- /dev/null
+++ b/changelogs/unreleased/rd-fix-case-sensative-email-conf-signup.yml
@@ -0,0 +1,5 @@
+---
+title: Fix case sensitive email confirmation on signup
+merge_request: 14606
+author: robdel12
+type: fixed
diff --git a/config/initializers/devise.rb b/config/initializers/devise.rb
index 3aed2136f1b..0ba0d791054 100644
--- a/config/initializers/devise.rb
+++ b/config/initializers/devise.rb
@@ -36,7 +36,7 @@ Devise.setup do |config|
   # Configure which authentication keys should be case-insensitive.
   # These keys will be downcased upon creating or modifying a user and when used
   # to authenticate or find a user. Default is :email.
-  config.case_insensitive_keys = [:email]
+  config.case_insensitive_keys = [:email, :email_confirmation]
 
   # Configure which authentication keys should have whitespace stripped.
   # These keys will have whitespace before and after removed upon creating or
diff --git a/spec/features/signup_spec.rb b/spec/features/signup_spec.rb
index b6367b88e17..917fad74ef1 100644
--- a/spec/features/signup_spec.rb
+++ b/spec/features/signup_spec.rb
@@ -24,6 +24,24 @@ feature 'Signup' do
       end
     end
 
+    context "when sigining up with different cased emails" do
+      it "creates the user successfully" do
+        user = build(:user)
+
+        visit root_path
+
+        fill_in 'new_user_name',                with: user.name
+        fill_in 'new_user_username',            with: user.username
+        fill_in 'new_user_email',               with: user.email
+        fill_in 'new_user_email_confirmation',  with: user.email.capitalize
+        fill_in 'new_user_password',            with: user.password
+        click_button "Register"
+
+        expect(current_path).to eq dashboard_projects_path
+        expect(page).to have_content("Welcome! You have signed up successfully.")
+      end
+    end
+
     context "when not sending confirmation email" do
       before do
         stub_application_setting(send_user_confirmation_email: false)